Nigel Nicolson

Nigel Nicolson, who died yesterday aged 87, was a Tory MP in the 1950s, a founding director of the publishers Weidenfeld and Nicolson, and the author or editor of numerous stylishly written books; he was, however, best known for Portrait of a Marriage, his account of the unorthodox union between his parents, Vita Sackville-West and Harold Nicolson.

The book, which contained a frank account of his parents' infidelities and homosexual affairs, caused a furore when it was published in 1973, and the author found himself the subject of much obloquy, accused of betraying his family and his class.

Private Eye parodied Nicolson's self-justifying foreword: his protestations of filial piety and a claim that he had consulted those whose opinions he most respected was appended by a footnote identifying his bank manager. A lewd ballad went the round of the clubs of St James's which ended: a lesbian's offspring begat by a queer/ But, self-made, a son of a bitch.

Yet in fairness, many felt he was justified in publishing an account which placed his mother's passionate affair with Violet Trefusis, which had lasted for three years, in the context of an enduringly successful marriage which had lasted 50. Moreover, Vita's own private account of her love for Violet (which her son had discovered in a Gladstone bag after her death) had, it seemed, been intended for publication.

Even Nicolson's critics, such as the writer Rebecca West (who declared that Vita's account should have been left in the Gladstone bag) did not attribute base motives to the book's author. His uncompromising integrity, indeed, was one of Nicolson's most endearing characteristics, mainly because it was as often applied to his own disadvantage as to that of others. A wise, kindly, somewhat shy man, he accepted, occasionally with bemusement, his privileged life and heritage, yet managed to avoid the self-centredness and snobbery that were such unattractive characteristics in his parents.

By nature nonconformist, he also had a stubborn streak of moral courage which led him to stand up for the truth even when it was inconvenient, a quality which lent him a natural nobility.

The older brother of the art historian Ben Nicolson, Nigel Nicolson was born in London on January 19 1917.

When he was about three, the family moved to Long Barn, a tumbledown 15th-century farmhouse near Knole, his mother's family home in Kent. In 1932, they moved permanently to Sissinghurst Castle and the house and its surrounding gardens became his parents' joint enterprise until their deaths.

Neither parent really understood their sons, although Harold Nicolson was an attentive father by the standards of the time. Their emotionally distant mother had no time for little boys, even refusing to be alone in the same room as her son Ben. As a result, the children spent most of their early years in the company of nannies and governesses. Nigel attributed his inability to sustain close relationships to his mother's coldness towards him.

He made his first acquaintance with Bloomsbury when, as a young boy, he was recruited to the dinner table to make the numbers up to 14, and placed opposite Lady Ottoline Morrell. Horrified by this apparition, he asked his mother in a whisper whether "that lady" wasn't a witch. "Of course she's a witch," said Clive Bell, to young Nicolson's mortification. "We have always known she was but nobody has dared say so." Aged 11, Nigel became Virginia Woolf's companion on butterfly hunting expeditions while she was writing Orlando, her fantasy about his mother.

Quentin Bell would later invite him to edit Virginia Woolf's letters, a project on which he collaborated with Joanne Trautmann, and which culminated in the publication, to great acclaim, of six volumes of correspondence between 1975 and 1980.

Vita Sackville-West's extraordinary relations included her mother, Lady Sackville, who had moved to White Lodge in Rottingdean, Hampshire, after leaving her husband in 1919. As children, Ben and Nigel spent many cold afternoons in her house waiting for lunch at 5pm, when it would be served by the under-gardener, the cook invariably having given notice that morning.

When Lady Sackville died in 1936, she bequeathed the house to Nigel; he would use the proceeds of its sale to help finance the launch of Weidenfeld and Nicolson and to buy the Shiants, some uninhabited islands in the Outer Hebrides which he would later pass on to his son Adam.

At the age of eight, Nicolson was propelled into the "concentration camps of boarding schools", first to Summerfields, Oxford, where he was taught by Cecil Day Lewis and Leonard Strong, the novelist. He then followed his brother Ben to Eton, where he fagged for Charles Villiers, the future chairman of British Steel, demonstrated his independence by refusing to be confirmed with the other boys, and won a place to read Modern History at Balliol, Oxford.

At Oxford, Nicolson's initial shyness made his first year a misery, but in his second year he began to come out of his shell. He spoke at Union debates and organised the university branch of his father's party, the National Labour Party, counting among his friends Denis Healey and Edward Heath. He also rowed for his college, but did little work and graduated with a Third.

In the early years of fascism, Nicolson had rather admired the dictators. For two years in succession he had joined Nazi friends in torchlit processions in Berlin. "There is something awfully naive and charming and sincere about [Hitler]," he wrote to his parents. "I cannot help reacting against all the negative criticism of the regime that one hears in England. Nag, nag nag, the whole time."

At Oxford his attitude changed and the Munich crisis clinched his recantation. In April 1939, having been rejected for the RAF, he enlisted in the Officer Cadet Reserve and after the declaration of war, was commissioned into the Grenadier Guards. He spent much of the war in reserve, but in 1942 was involved in the Tunisian campaign and was promoted to brigade intelligence officer in the rank of captain. In February 1944, his brigade was ordered to Italy, where they fought their way northwards, finally entering Austria on VE day.

His post as intelligence officer gave him an opportunity to observe, at close hand, the two Field Marshals, Montgomery, whom he disliked, and Alexander, whom he much admired. He was later forced to modify his opinions somewhat while researching his biography of Alexander, which was published in 1973, the same year as Portrait of a Marriage.

As he studied Alexander's papers, he came to like Alexander more as a man but began to detect a certain willingness to kow-tow to higher authority and take the easy way out in a crisis. Conversely, he came to admire Montgomery as a soldier and strategist, even as he disliked him as a man. His study, Alex: The Life of Field Marshal Earl Alexander of Tunis came to be widely regarded as Nicolson's best book.

At the end of the war in Europe, Nicolson's brigade was involved, as part of the British 5th Corps that occupied Carinthia, in the hand-over to the Red Army of about 40,000 anti-Soviet Cossack prisoners - men, women and children - and, to Tito, of some 30,000 Yugoslavs who had opposed him during the civil war. The majority of these people were either murdered or died in captivity.

The incident had its sequel in 1989 when Nicolson agreed to give evidence on behalf of Count Nikolai Tolstoy during his libel battle with Lord Aldington, staff officer at the time, whom Tolstoy had accused of organising the betrayal of the Cossacks, knowing their likely fate.

Nicolson had kept a record of events, from which it was clear that British soldiers had lied to their captives about their destination as they were herded on board cattle trucks that would transfer them to their enemies.

He recalled how, when Tito's partisans emerged to take control of the trains, the Yugoslavs "began hammering on the inside of the wagon walls, shouting imprecations, not at the partisans but at us, who had betrayed them. This scene was repeated day after day, twice a day. It was the most horrible experience of my life."

In agreeing to give evidence at the libel trial, Nicolson made it clear that, although he would support everything Tolstoy said about the enormity of the action, he could not accept his allegation that Aldington had arranged every detail of it or was mainly responsible for the decision.

The libel case was a traumatic experience for Nicolson. When he testified with painful honesty how, to his eternal shame, he had agreed to lie to the victims about their destination, he was asked by the unsympathetic judge whether the court was meant to suppose that he was an habitual liar. Aldington won the case, but never forgave Nicolson, a near neighbour, for appearing as a witness on the other side; and Nicolson found himself being snubbed by old friends who took Aldington's side.

Nicolson returned to England in July 1945 ahead of his battalion, as he had been commissioned to write the official history of the Grenadier Guards, which was published in 1949. When his father lost West Leicestershire in 1945, he was persuaded to enter politics and stood unsuccessfully for the same seat as a Conservative in 1950, and for Falmouth and Camborne in 1951. He was subsequently adopted for Bournemouth and entered Parliament in a by-election in 1952, with a majority of more than 14,000.

Nicolson was never comfortable with the Conservative tag. Yet he managed at first not to cause too much offence and in 1955 was re-elected with an increased majority.

In 1953 he had married Philippa, the daughter of Sir Gervais Tennyson-d'Eyncourt, and bought a house near Christchurch where a daughter was born in 1954 and a son in 1957.

The crunch came in 1956 when, having committed the almost unpardonable offence of supporting a Labour private member's Bill to abolish hanging, he then abstained in the vote of confidence in the government over Suez. His actions led to demands for his resignation from his constituency association. When he refused, his executive sent a telegram to the Prime Minister repudiating their member and pledging loyalty to the government.

In 1959, Nicolson, with the support of the chairman of the Tory Party, Lord Hailsham, insisted on the matter being put to a postal ballot of members. But in the meantime, he had become embroiled in a controversy of an entirely different nature.

In 1949, he had founded, with George Weidenfeld, the publishing firm of Weidenfeld and Nicolson. The firm struggled in its early years but the book that made the firm famous and contributed to Nicolson's debacle in Bournemouth was Vladimir Nabokov's Lolita, the controversial tale of a 12-year-old sex kitten with whom a middle-aged man falls in love.

Nicolson did not wholly believe in the book and had argued against its publication, but he was compelled to defend it when the firm took the decision to publish just as he was trying to save his political career. The two controversies peaked simultaneously and the postal ballot went against him by 3,762 votes to 3,671.

For four years from 1960, Nicolson worked full-time for the publishing firm, but resigned in 1964 before it became really successful, though he remained an outside director until it was sold to Anthony Cheetham in 1992.

Instead he wrote books which, in his estimation, probably contributed more to the success of the firm than he had by editing. His biography of Alexander and Portrait of a Marriage were serialised by the Sunday Times, and in 1977 Mary Curzon won the Whitbread Prize for biography. The firm also published his richly illustrated World of Jane Austen in 1991. Meanwhile, family responsibilities were taking up more of his time. After his mother Vita died in 1962, his father Harold Nicolson suffered a mental collapse and Nigel and his family moved to Sissinghurst to help care for him.

He had come to an arrangement with the Treasury and the National Trust whereby Sissinghurst was transferred to the Trust in part payment of death duties, with the family retaining tenancy of part of the building. With family income at a low ebb, he suggested to his father that he should publish his diaries and offered to edit them. The three volume diaries, published by Collins became best-sellers and Nicolson devoted most of the proceeds to sustaining his father until his death in 1968.

In his final homage to his parents he edited Vita and Harold, the letters of Vita Sackville-West and Harold Nicolson (1992). But by this time, many reviewers had had about all they could take of the Vita and Harold menage.

"Just when you think it is safe to stick your head above the parapet to get a gulp of air," wrote an exasperated Dirk Bogarde, "bang! crash! wallop! and once more one is cowed by salvoes of the dreaded V-3s, Vita, Violet and Virginia . . . Why does an elderly gentleman see fit to rake through the ashes of his parents' love and expose their very private thoughts to all and sundry, for, as Vita would have said, 'the delectation of the common herd'?"

In his later years, Nicolson turned to journalism and wrote the Spectator's Long Life column and a Time of My Life column for The Sunday Telegraph. His autobiography, Long Life, was published in 1997.

Nigel Nicolson's marriage ended in divorce in 1970 and he never attempted to marry again, although he continued to be a charming and entertaining companion to his many friends. He seemed to love being surrounded by tourists and became something of an institution at Sissinghurst, where he was known to lean out of his study window to invite visiting parties of Americans for tea.

Nigel Nicolson was appointed MBE in 1945.

He is survived by his son, the writer Adam Nicolson, and by two daughters.